﻿At most one of the bounds shall be of the type <em>IfcFaceOuterBound</em>.
<blockquote class="note">NOTE&nbsp; If the <em>IfcFace</em> is used within an <em>IfcFacetedBrep</em>, where all faces are implicitly planar and having a disctinct outer bound, exactly one of the bounds shall be of the type <em>IfcFaceOuterBound</em>.</blockquote>
